Luqman Qurata Aini, Hisae Hirata, Shinji Tsuyumu
The TonB-dependent transducer is required for plant pathogenicity in several plant pathogenic bacteria. In this study, we investigated the role of a putative TonB-dependent transducer, XAC4131, in Xanthomonas axonopodis pv. citri, the causal agent of citrus canker disease. A mutation in the XAC4131 gene caused a delay in the elicitation of the hypersensitive reaction in tobacco leaves. However, the pathogenicity in citrus leaves was similar to that of wild type. In hrp-inducing medium, XAC4131 controlled the expression of the hrp regulatory gene hrpG. Also, XAC4131 was involved in expression of the adjacent genes rpoEXAC4129 and XAC4130, which encode RpoE(XAC4129) and FecR-like protein, respectively. The results suggest that XAC4131 controls the expression of hrpG indirectly, probably via rpoEXAC4129 and XAC4130. Furthermore, we also demonstrated that transcription of rpoEXAC4129, XAC4130 and XAC4131 seems to be regulated by the Fur protein. © 2010 The Phytopathological Society of Japan and Springer.
Graduate School of Science and Technology, Shizuoka University, Shizuoka 422-8529, 836 Ohya, Suruga-ku, Japan; Faculty of Agriculture, Shizuoka University, Shizuoka 422-8529, 836 Ohya, Suruga-ku, Japan; Institute for Genetic Research and Technology, Shizuoka University, Shizuoka 422-8529, 836 Ohya, Suruga-ku, Japan; Faculty of Agriculture, Brawijaya University, Malang 65145, Jl. Veteran, Indonesia
